See “Non-GAAP Financial Measures” and reconciliation tables at the
end of this release.

“NRP started the year with a solid quarter of financial results,
continued robust cash flow generation and paid off $86 million of debt,”
commented NRP’s President and Chief Operating Officer, Craig Nunez.
“Additionally, in April we successfully refinanced our $100 million
revolving credit facility, extending the maturity from 2020 to 2023, and
we issued $300 million of 9.125% unsecured bonds due 2025, which will be
used along with cash on hand to redeem our existing $346 million of
10.5% bonds later this month, lowering our total debt by an additional
$46 million. We are pleased with the results of these transactions and
remain committed to continue strengthening our balance sheet to further
de-lever and de-risk the Partnership.”

NRP’s liquidity was $229.7 million at March 31, 2019, consisting of
$112.4 million of cash, $17.3 million of cash restricted for debt
repayment and $100.0 million of borrowing capacity available under its
credit facility. After giving effect to the refinancing transactions,
NRP’s liquidity as of March 31, 2019 would have been approximately $154
million, consisting of approximately $54 million of cash and $100
million of borrowing capacity. NRP’s consolidated Debt-to-Adjusted
EBITDA ratio at March 31, 2019, excluding the one-time, beneficial
Hillsboro settlement, was 2.9x, and after giving effect to the
refinancing transactions it will improve to 2.7x.

NRP’s cash flow cushion for the last twelve months ended March 31, 2019
was $32.5 million. Cash flow cushion represents the amount of free cash
flow left over after payment of mandatory debt amortizations and
preferred and common unit distributions.

NRP declared a cash distribution of $0.45 per common unit and a cash
distribution of $7.5 million on NRP’s Preferred Units for the first
quarter of 2019. In addition, NRP declared a one-time special cash
distribution of $0.85 per common unit to cover the common unitholders’
tax liability resulting from the sale of NRP’s construction aggregates
business in December 2018.

First Quarter Segment Results (Unaudited)

Operating Business Segments

Coal Royalty

Corporate

(In thousands)

and Other

Soda Ash

and Financing

Total

Three Months Ended March 31, 2019

Net income (loss) from continuing operations

$

42,607

$

11,682

$

(18,524

)

$

35,765

Adjusted EBITDA (1)

46,999

9,800

(4,350

)

52,449

Cash flow provided by (used in) continuing operations:

Operating activities

42,916

9,800

(29,884

)

22,832

Investing activities

697

—

—

697

Financing activities

—

—

(99,852

)

(99,852

)

Distributable cash flow (1)

43,613

9,800

(29,884

)

23,139

Free cash flow (1)

43,357

9,800

(29,884

)

23,273

Three Months Ended March 31, 2018

Net income (loss) from continuing operations

$

38,951

$

9,621

$

(22,286

)

$

26,286

Adjusted EBITDA (1)

44,293

12,250

(4,336

)

52,207

Cash flow provided by (used in) continuing operations:

Operating activities

38,793

10,153

(31,532

)

17,414

Investing activities

1,143

2,097

—

3,240

Financing activities

—

—

(26,844

)

(26,844

)

Distributable cash flow (1)

39,936

12,250

(31,532

)

20,654

Free cash flow (1)

39,280

12,250

(31,532

)

19,998

_________________________

(1)

See “Non-GAAP Financial Measures” and reconciliation tables at the
end of this release.

Coal Royalty and Other

Solid first quarter 2019 results were driven by continued stable
performance from NRP’s metallurgical and thermal coal properties. First
quarter 2019 revenues, net income and Adjusted EBITDA were positively
impacted by higher average coal royalty revenue per ton and increased
coal overriding royalty revenues from NRP’s Williamson property in the
Illinois Basin. In addition, NRP recorded $2.8 million of revenue from
its Hillsboro property in the first quarter of 2019, compared to zero in
the prior year quarter, following the settlement of the Foresight
litigation in the fourth quarter of 2018. Consistent with the prior year
quarter, approximately 65% of NRP’s coal royalty revenues and
approximately 55% of its coal royalty production was derived from
metallurgical coal during the three months ended March 31, 2019.

Distributable cash flow and Free cash flow increased compared to the
prior year quarter primarily as a result of the timing of cash
collections and the collection of lease amendment fees in the first
quarter of 2019.

Soda Ash

Soda Ash segment operating performance increased compared to the prior
year quarter primarily as a result of an increase in production and
sales volumes and higher domestic and international sales prices
compared to the prior year quarter.

Adjusted EBITDA, Distributable cash flow and Free cash flow decreased
$2.5 million compared to the prior year quarter as a result of a lower
cash distribution received from Ciner Wyoming in the first quarter of
2019.

Corporate and Finance

Corporate and Finance segment results improved compared to the prior
year quarter primarily due to lower interest expense as a result of
NRP’s continued debt repayment.

Conference Call

A conference call will be held today at 10:00 a.m. ET. To join the
conference call, dial (844) 379-6938 and provide the conference code
55454892. Investors may also listen to the call via the Investor
Relations section of the NRP website at www.nrplp.com.
To access the replay, please visit the Investor Relations section of
NRP’s website.

Company Profile

Natural Resource Partners L.P., a master limited partnership
headquartered in Houston, TX, is a diversified natural resource company
that owns, manages and leases a diversified portfolio of mineral
properties in the United States including interests in coal, industrial
minerals and other natural resources. A large percentage of NRP’s
revenues are generated from royalties and other passive income. In
addition, NRP owns an equity investment in Ciner Wyoming, a trona/soda
ash operation.

For additional information, please contact Tiffany Sammis at
713-751-7515 or tsammis@nrplp.com.
Further information about NRP is available on the partnership’s website
at http://www.nrplp.com.

Forward-Looking Statements

This press release includes “forward-looking statements” as defined
by the Securities and Exchange Commission. All statements, other than
statements of historical facts, included in this press release that
address activities, events or developments that the partnership expects,
believes or anticipates will or may occur in the future are
forward-looking statements. These statements are based on certain
assumptions made by the partnership based on its experience and
perception of historical trends, current conditions, expected future
developments and other factors it believes are appropriate in the
circumstances. Such statements are subject to a number of assumptions,
risks and uncertainties, many of which are beyond the control of the
partnership. These risks include, but are not limited to, commodity
prices; decreases in demand for coal, aggregates and industrial
minerals, including trona/soda ash; changes in operating conditions and
costs; production cuts by our lessees; unanticipated geologic problems;
our liquidity, leverage and access to capital and financing sources;
changes in the legislative or regulatory environment, litigation risk,
and other factors detailed in Natural Resource Partners’ Securities and
Exchange Commission filings. Natural Resource Partners L.P. has no
obligation to publicly update or revise any forward-looking statement,
whether as a result of new information, future events or otherwise.

Non-GAAP Financial Measures

“Adjusted EBITDA” is a non-GAAP financial measure that we
define as net income (loss) from continuing operations less equity
earnings from unconsolidated investment, net income attributable to
non-controlling interest and gain on reserve swap; plus total
distributions from unconsolidated investment, interest expense, net,
debt modification expense, loss on extinguishment of debt, depreciation,
depletion and amortization and asset impairments. Adjusted EBITDA should
not be considered an alternative to, or more meaningful than, net income
or loss, net income or loss attributable to partners, operating income,
cash flows from operating activities or any other measure of financial
performance presented in accordance with GAAP as measures of operating
performance, liquidity or ability to service debt obligations. There are
significant limitations to using Adjusted EBITDA as a measure of
performance, including the inability to analyze the effect of certain
recurring items that materially affect our net income (loss), the lack
of comparability of results of operations of different companies and the
different methods of calculating Adjusted EBITDA reported by different
companies. In addition, Adjusted EBITDA presented below is not
calculated or presented on the same basis as Consolidated EBITDA as
defined in our partnership agreement or Consolidated EBITDDA as defined
in Opco’s debt agreements. Adjusted EBITDA is a supplemental performance
measure used by our management and by external users of our financial
statements, such as investors, commercial banks, research analysts and
others to assess the financial performance of our assets without regard
to financing methods, capital structure or historical cost basis.

“Distributable cash flow” or “DCF” is a non-GAAP financial
measure that we define as net cash provided by (used in) operating
activities of continuing operations plus distributions from
unconsolidated investment in excess of cumulative earnings, proceeds
from sales of assets, including sales of discontinued operations, and
return of long-term contract receivables (including affiliate); less
maintenance capital expenditures and distributions to non-controlling
interest. DCF is not a measure of financial performance under GAAP and
should not be considered as an alternative to cash flows from operating,
investing or financing activities. DCF may not be calculated the same
for us as for other companies. In addition, Distributable cash flow is
not calculated or presented on the same basis as distributable cash flow
as defined in our partnership agreement, which is used as a metric to
determine whether we are able to increase quarterly distributions to our
common unitholders. Distributable cash flow is a supplemental liquidity
measure used by our management and by external users of our financial
statements, such as investors, commercial banks, research analysts and
others to assess our ability to make cash distributions and repay debt.

“Free cash flow” or “FCF” is a non-GAAP financial measure that
we define as net cash provided by (used in) operating activities of
continuing operations plus distributions from unconsolidated investment
in excess of cumulative earnings and return of long-term contract
receivables (including affiliate); less maintenance and expansion
capital expenditures, cash flow used in acquisition costs classified as
financing activities and distributions to non-controlling interest. FCF
is calculated before mandatory debt repayments. Free cash flow is not a
measure of financial performance under GAAP and should not be considered
as an alternative to cash flows from operating, investing or financing
activities. Free cash flow may not be calculated the same for us as for
other companies. Free cash flow is a supplemental liquidity measure used
by our management and by external users of our financial statements,
such as investors, commercial banks, research analysts and others to
assess our ability to make cash distributions and repay debt.

“Free cash flow excluding discontinued operations and one-time
beneficial items” is a non-GAAP financial measure that we define as
Free cash flow excluding discontinued operations and one-time beneficial
items.Free cash flow excluding discontinued operations and
one-time beneficial items is not a measure of financial performance
under GAAP and should not be considered as an alternative to cash flows
from operating, investing or financing activities. Free cash flow
excluding discontinued operations and one-time beneficial items may not
be calculated the same for us as for other companies. Free cash flow
excluding discontinued operations and one-time beneficial items is a
supplemental liquidity measure used by our management to assess our
ability to make cash distributions and repay debt.

“Cash flow cushion” is a non-GAAP financial measure that we
define as Free cash flow excluding discontinued operations and one-time
beneficial items less mandatory Opco debt amortization payments,
preferred unit distributions and common unit distributions. Cash flow
cushion is not a measure of financial performance under GAAP and should
not be considered as an alternative to cash flows from operating,
investing or financing activities. Cash flow cushion is a supplemental
liquidity measure used by our management to assess the Partnership’s
ability to make or raise cash distributions to our common and preferred
unitholders and our general partner and repay debt or redeem preferred
units.

“Return on capital employed” or “ROCE” is a non-GAAP financial
measure that we define as Net income from continuing operations plus
interest expense divided by the sum of equity excluding equity of
discontinued operations, and debt. Return on capital employed should not
be considered an alternative to, or more meaningful than, net income or
loss, net income or loss attributable to partners, operating income,
cash flows from operating activities or any other measure of financial
performance presented in accordance with GAAP as measures of operating
performance, liquidity or ability to service debt obligations. Return on
capital employed is a supplemental performance measure used by our
management team that measures our profitability and efficiency with
which our capital is employed. The measure provides an indication of
operating performance before the impact of leverage in the capital
structure.

“Return on capital employed excluding discontinued operations and
one-time beneficial items” is a non-GAAP financial measure that we
define as Return on capital employed excluding one-time beneficial
items. Return on capital employed excluding discontinued operations and
one-time beneficial items should not be considered an alternative to, or
more meaningful than, net income or loss, net income or loss
attributable to partners, operating income, cash flows from operating
activities or any other measure of financial performance presented in
accordance with GAAP as measures of operating performance, liquidity or
ability to service debt obligations. Return on capital employed
excluding discontinued operations and one-time beneficial items is a
supplemental performance measure used by our management team that
measures our profitability and efficiency with which our capital is
employed excluding the impact of one-time beneficial items. The measure
provides an indication of operating performance before the impact of
leverage in the capital structure and excluding the impact of one-time
beneficial items.